Automatic saw filing machine



Dec' 23 1941. F. `H. DALE 2,267,553

AUTOMATIC SAW FILING MACHINE I l 2 Sheets-Sheet l Dec. 23, 1941. F 'H. DALE AUTOMATIC SAW FILING MACHINE Filed Au'g. 26, 1939 2 Sheets-Sheet 2 Patented Dec. 23, 1941 AUTOMATIC SAW FILING MACHINE Frederick H. Dale, Manhattan, Kans., assignor of one-half to Rolla E. Long, Manhattan, Kans.

Application August 26, 1939, Serial No.l 292,087

(Cl. 'Y6-34) 2 Claims.

This invention relates to saw filing machines of the power driven type and has for its primary object the provision of equipment for filing the teeth of saws through the employment of automatic equipment which is effective in operation, simple and durable in construction, not intricate or complicated and efficient to the end that the teeth of the saw being treated are effectively formed and filed with a minimum amount of attention from the operator.

One of the important aims of this invention is to provide an automatic saw ling machine wherein is incorporated unique and effective means for periodically gripping the saw adjacent to the zone of treatment so that high speed cutting may occur without injury to the saw and as the teeth of the saw remain in proper alignment.

This invention has for a still further object the` provision of a sawling machine wherein is embodied a special file holder and means for mounting said holder so that it will travel vertically toward and from the saw being filed and transversely there-across as associated gripping jaws are moved to and from a saw engaging position for the purpose of allowing a periodic forward movement of the saw as the le is lifted therefrom.

A further object of this invention is the provision of a saw filing machine capable of being set and allowed to continuously operate without the attention of an operator and which comprises means for holding and actuating a iile, means for periodically gripping the saw being treated, means for carrying and advancing the saw in step-by-step movements, and mechanism for interconnecting all of the aforesaid means with a motor or similar source of power.

This invention contemplates other objects in addition to those set down above and these additional aims will appear during the course of the following specification, referring to the accompanying drawings, wherein:

Figure 1 is a top plan view of a saw filing machine made in accordance with the present invention.

Fig. 2 is a vertical, sectional view through the machine taken on line II-II of Fig. 1.

Fig. 3 is a vertical, cross sectional view through the machine taken on line III-III of Fig. 2.

Fig. 4 is a horizontal, fragmentary, sectional view through a portion of the machine taken on line IV-IV of Fig. 2, and

Fig. 5 is a fragmentary, perspective, detailed View of the sectional rail for the saw carrier.

The illustrated embodiment of the invention that has been chosen for description comprises a frame 8 that is in the form of a bench or table, the top I0 of which is supported above the iioor.

A shelf I2 carries an ordinary electric motor I4 that has a pulley wheel I6 mounted upon ther motor shaft I8. A belt 20 passes over pulley I6 and a relatively large grooved pulley 22 that is mounted upon shaft 24 journaled in bearings 26 mounted upon top I6 of frame 8. Shaft24 has pinion 28 keyed or otherwise secured thereto for rotation therewith, and gear 30` is in mesh with this said pinion 28. Gear 30 is mounted upon shaft 32 which, like shaft 24, is journaled in bearings 26. A crank 34 is secured to one end of shaft 32; this crank 34 is relatively short and the free end thereof is fastened to a iiat connecting rod 36 and to the upper end of a link 38. The lower end of link 38` is pivotally secured as at 40 to rocker arm 42 that swings about the axis of pintle 44 carried by bracket 46. Pintle 44 is intermediate the ends of rocker arm 42 and the end of said rocker arm opposite to that connected to the lower end of link 38 is pivotally joined as at 48 to a vertically reciprocating rod 50 mounted in tube 52.

While the lower end of rod 50 is joined to rocker arm 42, the upper end thereof is secured to coupling 54 which serves as a medium of joining one end of spaced apart polygonal bars 56 to the upper end of rod 5U. The other ends of these said bars 576 are pivotally carried by the upper portions of two of the aforesaid bearings 26. Reference to Figure 1 will reveal the manner in which these said ends of bars 56 are pivotally joined to bearings 26 through the use of stub shafts 58. The upper end of link 38 is disposed between bars 56 and the4 connecting rod 36 rests between these bars 56 so that its bifurcated end 60 may engage they file holder designated generally by the numeral 62. This le holder comprises a head 64 slidably mounted upon bars 56. Caps 66 are held in place by machine bolts 68, and the openings through head 64 and caps 66 are of the same cross-sectional contour as the similar contour of bars 56 so that rotation is not permitted and lateral displacement of file 10 therefore is reduced to a minimum.

File 1U is mounted in a pair of specially formed blocks 12, one. of which is adjacent to each end of head 64.'. Each block 'l2 has a cavity 14 formed therein for the reception of a depending carried in transverse openings formed through blocks 12.

A set screw 84 adjustably mounted in at least one of blocks 12 permits the operator to dispose the converging sides of file 10 in the proper position for liling the teeth 86 of saw 88.

The saw carrier comprises a turn-table 90 mounted directly upon the top I of frame 8 and movable about a pivot bolt 92. A sectional rail 94 supports plate 96 upon which saw 88 is directly mounted. Thumb nuts 98 in screw-threaded engagement with bolts |00 which pass through slots |02, cooperate with clips |04 in holding saw 88. Plate 96 has a series of channeled brackets |05, each of which is in slidable engagement with the web of rail 94; thus plate 96 with its saw 88 may be moved longitudinally along rail 94 as the ling operation progresses. In some instances it is desirable to remove rail 94 and to facilitate handling the machine this rail 94 is made sectional. 'Ihe adjacent ends of rail 94 are formed as shown in Fig. 5 so that the fixture |06 may serve to hold the two sections of the rail together as the plate 98 is mounted thereon. Notches |08 receive xture |08 as shown in Fig. 2.

Turn-table 90 has an arcuate slot ||0 formed therein which is concentric with the axis of rotation about pivot bolt 92. A lock bolt and nut assembly ||2 carried by top I0 serves to secure turn-table 90 in the desired position after pointer ||4 has been associated with the desired designation on scale |6 which is etched or otherwise formed on the upper face of turn-table 90 close to slot I0.

It is important that saw 88 be rigidly gripped adjacent to the tooth being acted upon by le 10 and since there is means in this machine for advancing saw 88, the gripping elements must periodically engage the saw while le 10 travels through its path of movement in one direction. The gripping means illustrated in the accompanying drawings comprises a stationary jaw ||8 mounted directly upon turn-table 90 and braced against displacement by member |20 and a movable jaw |22 pivotally mounted upon turn-table 90 through the medium of pin |24 and ears |26. Jaw |22 is periodically moved about its pivotal connection by a toggle link |28, one section |30 of which is adjustably attached to jaw |22 through the medium of screw-threads |32 which, when pin |34 is withdrawn, will allow rotating section |30 to increase or decrease the distance between the edge of jaw |22 and the pivotal connection |34 between section |36 of the toggle link and turn-table 90. Section |36 of toggle link |28 is in the form of a bell crank lever, the knee of which is pivotally mounted as pivotal connection |34 joins one free end to section |30. The other free end of this bell crank lever section |36 extends into yoke |38 that is carried by arm |40. Yoke |38 is wide enough to permit freedom of movement of section |36 when turn-table 90 is moved about its axis of rotation which is directly above the yoke. This arm is pivotally secured as `at |42 to a fixture |44, mounted on the under side of top I0 and a link |46 joins one end of arm |40 with rocker arm 42. Pin |48 serves to join rocker arm 42 to arm 40 and the position of pin |48 is to one side of pintle 44 so that the parts will operate as hereinafter set down.

Means for imparting step-by-step movement to the saw carrier is operated by head 64 coming into contact with plate |50 which lies in the path of travel of head 64 when the latter is moved upwardly by bars 56. Plate 50 is carried by the lower end of screw |52 that passes through foot 54 and which has a head |56 thereon. A spring |58 ldisposed between head |56 and foot |54 maintains tension upon screw |52 and thereby precludes accidental maladjustment. Foot |54 is integral with arm |60 upon the free end of which is mounted dog |62; one end of dog |62 is formed to progressively engage teeth 86 of saw 88 and a spring |64 yieldably maintains this said free end of dog |62 against the teeth of the saw.

Foot and arm |54 and |60 respectively, swing about the axis of pin |66 as a unit. Spring |68 yieldably maintain these parts at one end of their path of travel and a stop bolt |10 adjustably carried by a portion of standard |12, limits the movement of arm |60 in one direction. There are two standards |12 mounted upon turn-table so that in the event the mechanism for imparting step-by-step movement to the saw carrier is to be disposed so that the saw is forced along a direction opposite to that indicated by the arrow in Fig. 3, the parts just described may be removed and mounted upon the standard 12 which is shown in Fig. 3 to be without the necessary elements to act upon the saw.

The drawings illustrate an ordinary hand saw 88 being sharpened but it is obvious to one skilled in the art that band saws or saws of other characters than that illustrated, may be sharpened and teeth formed therein by the machine embodying this invention. Turntable 90 is shown positioned so that rail 94 extends laterally from frame 8 in a line perpendicular to the longitudinal axis of said frame and perpendicular to the path of travel of the le holder 62. Obviously, turn-table 90 may be positioned to cause file 10 to act upon teeth 86 in the desired way as is known in the art.

The operation of an automatic saw filing machine such as has been described above is as follows:

Saw 88 is positioned on plate 96 and beneath le 10 so that the latter will form teeth or engage the edges of the saw forming the teeth at the desired angle. Turn-table 90 is secured in place by lock ||2 and screws |52 and |10 are set so that saw 88 is advanced in a step-by-step movement to allow ile 10 to progressively enter ybetween each of the successive teeth 86 of the saw.

As the motor rotates crank 32, head 64 of the le holder will reciprocate upon bars 56. Rocker arm 42, being operated by link 38 so that rod 50 will move vertically, will cause the ends of bars 56 to raise and lower about the axes of aligned stub shafts 58. 'Ihe timing of the parts which raise and lower bars 56 and move head 64 is such as to cause the le 10 to work upon the teeth of the saw when the le is being moved in the direction of the arrow shown in Fig. 2. When the le is so moving, bars 56 are at the lower end of their vertical path of travel. When i'lle 10 is moving in the direction opposite to the arrow shown in Fig. 2, bars 56 are at the upper end of their vertical path of travel and therefore, file is not engaging the saw. When bars 56 are at the upper end of their path of travel and when le 10 is being moved back to the point of beginning, and in a direction opposite to the arrow shown in Fig. 2, the means for imparting step-by-step movement to saw 88 is forcing the saw to a position where file 10 will engage the next tooth. Obviously, this movement is imparted to the saw by plate |50 being .engaged by head 64. The raising of this plate |50 to move foot and arm |54 and |60 about the axis of element |66 will force dog |62 in the direction of the arrow shown in Fig. 3 and thereby move saw 88 and plate 96 longitudinally a short distance which is governed by the amount of upward travel imparted to plate |50. This movement may be varied by adjusting bolt |52. It is imperative that saw 88 be rigidly held while file 'l0 is moving in the direction of the arrow shown in Fig. 2 and while the cutting action is taking place. Saw 88 travels along between jaws ||8 and |22 and when bars 5B are at their lower end of their vertical path of travel and while file 10 is being drawn in the direction of the arrow, movable jaw |22 is cooperating with jaw I8 to grip saw 88 at a point between plate 96 and the le. Parts 38, |40 and al1 of toggle link |28 are arranged so that said link |28 is forcing jaw |22 against the saw at the proper aforesaid time. A downward movement on the part of yoke |38 will draw the free end of the bell crank lever |36 about the axis of pin |34 and section |30 of the toggle link |28 will be drawn tight so as to force movable jaw |22 against the saw. As soon as the parts are disposed so that dog |62 is brought into play to move the saw longitudinally, jaws ||8 and |22 have released their hold by the breaking of toggle link |28 so as to withdraw movable jaw |22 from a position against the saw.

Maniiestly the foregoing detailed description of the illustrated embodiment of the invention and minute explanation of the operation of my automatic saw filing machine will permit one skilled in the art to understand the invention as claimed herein. It is conceivable that machines for sawing les having physical characteristics other than those shown and explained may be made to embody the concepts of the invention without departing from the scope of the appended claims.

Having thus described the invention, what is claimed as new and desired to be secured by Letters Patent is:

l. In a saw filing machine, a saw carrier; a

file holder; means` for imparting reciprocating movement to the 1'ile holder; a turn table having a slot; a pair of holding jaws for the same mounted on the turn table, one of said jaws being rigidly mounted on the turn table, the other of said jaws being pivotally mounted on the turn table for movement toward and from the rigid jaw; and mechanism for positioning said jaws into gripping engagement with the saw while the iile holder moves through its path of travel in one direction, comprising a motor, a bell-crank lever pivotally mounted on the turn table, a section connecting one end of said bell-crank lever and the pivotal jaw and. having pivotal connection with the bell-crank lever, a yoke provided with an elongated slot in operative engagement with the other end of said bell-crank lever, said lever being projected through the slot in the turn table to engage the yoke, and linkageoperably connecting the motor and said yoke, said other end of the bell-crank lever being disposed in the said slot for movement therealong as the turntable is rotated whereby motion may be imparted to said mechanism when the turntable is in one of a number of different positions.

2. In a saw ling machine, a saw carrier; a le holder; a turn table having a slot; a pair of holdf ing jaws for the same mounted on one side of the turn table, one of said jaws being rigidly mounted on the one side of the turn table, the other of said jaws being pivotally mounted on the one side of the turn table for movement toward and from the rigid jaw; and'mechanism for positioning said jaws in gripping engagement with the saw while the file holder moves through its path of travel in one direction, comprising a motor, a bell-crank lever pivotally mounted in av vertical position on the one side of the turn table, a section connecting one end of said bell-crank lever and the pivotal jaw and having pivotal connection with the bell-crank lever, a yoke adja cent the other side of the turn table and provided with an elongated slot in operative engagement with the other end of said bell-crank lever, said lever being projected through the said slot in the turn table to engage the yoke at a point near the axis of the turn table, and linkage operably connecting the motor and said yoke, said other end of the bell-crank lever being disposedin the said slot for movement therealong as the turn table is rotated whereby motion may be imparted to said mechanism when the turn table is in one of a number of different positions.

FREDERICK H. DALE. 

